• Journal of the Ergonomics Society of Korea
• /
• v.30 no.6
• /
• pp.705-713
• /
• 2011

Objective: The aim of this study is to compare results of emotion recognition by several algorithms which classify three different emotional states(happiness, neutral, and surprise) using physiological features. Background: Recent emotion recognition studies have tried to detect human emotion by using physiological signals. It is important for emotion recognition to apply on human-computer interaction system for emotion detection. Method: 217 students participated in this experiment. While three kinds of emotional stimuli were presented to participants, ANS responses(EDA, SKT, ECG, RESP, and PPG) as physiological signals were measured in twice first one for 60 seconds as the baseline and 60 to 90 seconds during emotional states. The obtained signals from the session of the baseline and of the emotional states were equally analyzed for 30 seconds. Participants rated their own feelings to emotional stimuli on emotional assessment scale after presentation of emotional stimuli. The emotion classification was analyzed by Linear Discriminant Analysis(LDA, SPSS 15.0), Support Vector Machine (SVM), and Multilayer perceptron(MLP) using difference value which subtracts baseline from emotional state. Results: The emotional stimuli had 96% validity and 5.8 point efficiency on average. There were significant differences of ANS responses among three emotions by statistical analysis. The result of LDA showed that an accuracy of classification in three different emotions was 83.4%. And an accuracy of three emotions classification by SVM was 75.5% and 55.6% by MLP. Conclusion: This study confirmed that the three emotions can be better classified by LDA using various physiological features than SVM and MLP. Further study may need to get this result to get more stability and reliability, as comparing with the accuracy of emotions classification by using other algorithms. Application: This could help get better chances to recognize various human emotions by using physiological signals as well as be applied on human-computer interaction system for recognizing human emotions.

• Journal of Korean Biological Nursing Science
• /
• v.23 no.1
• /
• pp.22-30
• /
• 2021

Purpose: This descriptive study aimed to investigate heart rate variability (HRV) according to sex and to elucidate the influence of negative emotion such as levels of stress, anxiety and depression on HRV among Korean college students based on a neurovisceral integration model. Methods: A descriptive study design was used. Eighty-six healthy college students participated in the study. Resting HRV and standing HRV on orthostatic stimulation were measured for 5 minutes during 4-6 p.m. in the afternoon. Levels of stress, anxiety and depression were assessed using the Global assessment of recent stress, State-Trait Anxiety Inventory and Beck Depression Index, respectively. Results: Out of the 86 students, 47 (54.7%) were men and 39 (45.3%) were women. Root mean square of the differences between adjacent RR intervals (RMSSD) and normalized high frequency (nHF) on standing HRV were significantly lower in men than in women (p= .005, p= .019, respectively). Male gender (β= 0.30, p= .013), higher level of stress (β= -0.36, p= .009) and lower level of depression (β = 0.30, p= .044) exerted a significant influence on decreased nHF in the multiple regression analysis. Conclusion: We suggest that men are more vulnerable to having reduced vagal activity on HRV than women. Since male gender, higher level of stress and lower level of depression level influenced decreased vagal activity, strategies are needed to improve stress and depression rather than anxiety especially for men, which contribute to promoting HRV to prevent cardiac health diseases.

• Journal of Biomedical Engineering Research
• /
• v.43 no.1
• /
• pp.27-34
• /
• 2022

Drunk driving defines a driver as unable to drive a vehicle safely due to drinking. To crack down on drunk driving, alcohol concentration evaluates through breathing and crack down on drinking using S-shaped courses. A method for assessing drunk driving without using BAC or BrAC is measurement via biosignal. Depending on the individual specificity of drinking, alcohol evaluation studies through various biosignals need to be conducted. In this study, we measure biosignals that are related to alcohol concentration, predict BrAC through SVM, and verify the effectiveness of the S-shaped course. Participants were 8 men who have a driving license. Subjects conducted a d2 test and a scenario evaluation of driving an S-shaped course when they attained BrAC's certain criteria. We utilized SVR to predict BrAC via biosignals. Statistical analysis used a one-way Anova test. Depending on the amount of drinking, there was a tendency to increase pupil size, HR, normLF, skin conductivity, body temperature, SE, and speed, while normHF tended to decrease. There was no apparent change in the respiratory rate and TN-E. The result of the D2 test tended to increase from 0.03% and decrease from 0.08%. Measured biosignals have enabled BrAC predictions using SVR models to obtain high Figs in primary and secondary cross-validations. In this study, we were able to predict BrAC through changes in biosignals and SVMs depending on alcohol concentration and verified the effectiveness of the S-shaped course drinking control method.

• Journal of People, Plants, and Environment
• /
• v.24 no.1
• /
• pp.107-117
• /
• 2021

Background and objective: The purpose of this study is to investigate the effect of a forest healing program in terms of depression, neuropsychological and physiological benefits for the elderly. Methods: For this purpose, we developed a forest therapy program for the elderly who are vulnerable to dementia and conducted a total of 11 sessions of forest therapy activities in a forest once a week. We measured the changes in depression, resting-state Electroencephalography(EEG) and heart rate variability (HRV) before and after the program. There were 60 subjects aged over 65 yesrs old. 30 subjects participated in the forest therapy program, and the other were in the control group. The Geriatric Depression Scale was used to measure the level of depression, neuroNicle FX2 (Laxtha, Korea) was used to measure the resting-state EEG, and photoplethymogram (ubpulse T1, Laxtha, Korea) was used to measure the HRV. Results: The results showed that the depression index of the experimental group improved with statistical significance after the program (experiment group = 3.267 decrease of the mean). In the EEG measurement, the alpha-peak frequency at rest (experimental group = 0.227 Hz increase of the mean) was improved (mean increase = 0.23 in the experimental group, p < .05). The high frequency of HRV, which represents the parasympathetic nerve activity of the body's autonomous response, was also significantly improved (mean increase = 0.396 in the experimental group, p < .05). Conclusion: The results suggest that the forest therapy program can reduce the cognitive, psychological and physical risk factors of dementia for the elderly at risk of cognitive decline. Therefore, forest therapy activities may be suitable for the prevention of dementia in the elderly.

• Sleep Medicine and Psychophysiology
• /
• v.8 no.1
• /
• pp.52-58
• /
• 2001

Objectives: An Increased level of psychophysiologic arousal and diminished physiologic flexibility would be observed in patients with panic disorder compared with a normal control group. We investigated the differences of psychophysiologic response between patients with panic disorder and normal control to examine this hypothesis. Methods: Ten Korean patients with panic disorder who met the diagnostic criteria of DSM-IV were compared with 10 normal healthy subjects. In psychological assessment, levels of anxiety and depression were evaluated by State-Trait Anxiety Inventory, Beck's Depression Inventory and Hamilton Rating Scale For Anxiety and Depression. Heart rate, respiration rate, electrodermal response, and electromyographic activity were measured by biofeedback system (J & J I-330 model) to determine psychophysiologic responses on autonomic nervous system. Stressful tasks included mental arithmetic, video game, hyperventilation, and talking about a stressful event. Psychophysiologic responses were measured according to the following procedures : baseline(3 min)-mental arithmetic (3 min)-rest (3 min)-video game (3 min)-rest (3 min)-hyperventilation (3 min)-rest (3 min)-talking about a stressful event (3 min). Results: The baseline level of anxiety and depression, electrodermal response (p=.017), electromyographic activity (p=.047) and heart rate (p=.049) of patients with panic disorder were significantly higher than those of the normal subject group. In electrodermal response, patient group had significantly higher startle response than the control group during hyperventilation (p=.001). Startle and recovery responses of heart rate in the patient group were significantly lower than responses in the control group during mental arithmetic (p=.007, p=.002). In electrodermal response of the patient group, startle response was significantly higher than recovery response during mental arithmetic (p=.000) and video game task (p=.021). Recovery response was significantly higher than startle response in respiratory response during hyperventilation. Conclusion: The results showed that patients with panic disorder had higher autonomic arousal than the control group, but the physiologic flexibility was variable. We suggest that it is helpful for treatment of panic disorder to decrease the level of autonomic arousal and to recover the physiologic flexibility in certain stressful event.

• Journal of Oriental Neuropsychiatry
• /
• v.25 no.1
• /
• pp.1-12
• /
• 2014

Objectives: In this study, the meditation programs (${\alpha}$ version), which are properly coordinated according to the motion, breathing, and relaxation, are evaluated and researched upon to have positive effects on stress and in the area of psychology. Methods: Approved by the Clinical Trials Deliberation Committee in Oriental Medicine, Dongguk University, Ilsan Hospital, this study collected data according to the applicant's consents, demographic information and anthropometry for the Sasang Constitutional diagnosis. Sasang Constitutional diagnosis measured the beta tools by Institute of Oriental Medicine and a decision tree was made for the Sasang Constitutional questionnaires. The STAI, STAXI, BDI, and HRV were measured before and after the meditation in order to compare the effects of meditation according to Sasang Constitution. The HRV was used as a ProComP KM Tech (co). Results: 1) The positive changes available in the Time-domain analysis of heart rate variability assessment showed that the peace of mind is increased. By analyzing the Sasang constitution, So-eum In's peace of mind included a physical stability of the autonomic nervous system. 2) According to the psychological scale evaluation, each depression scale, trait anger, anger-in, state anxiety and trait anxiety index proved significantly positive effects. By analyzing the Sasang constitution, Eun-In which involved So-eum In and Tae-eum In, had positive effects. 3) The psychological scale changed the group of diagnosed depression or anxiety, it did not mean that the psychological scale changes in the depression group, but the index of the anxiety group had been significantly reduced. This program had clinical effects for anxious patients and Eum-In which involved Tae-eum In and So-eum In according to the analysis of Sasang constitution. 4) Correlations between the gender of each psychological scale showed that women have overall low correlations, but, there were no significant changes. Conclusions: The meditation program developed by adequately mixing Action, relaxation and breathing shows that it is effective for overall Eum-in physical and mental relaxation and concentration. In the future, It will have to be developed Meditation program to show the same effect for all people.